戊菌唑在黄瓜和土壤中的残留

为探明戊菌唑在黄瓜中的安全性,采用气相色谱-电子捕获器法对戊菌唑在江苏南京、北京和吉林长春3个试验点黄瓜和土壤中的残留消解动态和最终残留进行了研究。结果表明,在0.01 mg/kg、0.10 mg/kg和1.00 mg/kg 3个添加水平下,戊菌唑在黄瓜中的添加回收率为82.5%～94.2%,相对标准偏差为4.8%～7.5%;在土壤中平均回收率为81.2%～93.2%,相对标准偏差为6.2%～9.1%;戊菌唑在黄瓜和土壤中的最低检测浓度均为0.01 mg/kg。戊菌唑在3个试验点黄瓜中的半衰期为1.6～1.9 d,在土壤中的半衰期为1.8～2.3 d。戊菌唑按低剂量(57.0 g/hm2,a.i.)或高剂量(85.5 g/hm2,a.i.)施药2次或3次,在最后一次施药1 d、3 d和5 d后采收,黄瓜中戊菌唑的残留量均低于0.080 mg/kg。按试验推荐施药剂量和次数施用戊菌唑,参照CAC、欧盟或日本制订的黄瓜中戊菌唑的最大残留限量标准(0.1 mg/kg),所采收的黄瓜是安全的。

Residues of penconazole in cucumber and soil

To investigate the safety of penconazole in cucumber,degradation and final residues of penconazole in cucumber and soil on three experimental sites(Nanjing,Beijing and Changchun) were determined by means of meteorological chromatographic-electronic capture device.At the penconazole addtion levels of 0.01 mg/kg,0.10 mg/kg and 1.00 mg/kg,the recoveries in cucumbers were 82.5%-94.2%,with RSD 4.2%-7.5%,and the recoveries in soil were 81.2%-93.2%,with RSD of 6.2%-9.1%.The limits of detection of penconazole in cucumber and soil were both 0.01 mg/kg.The half-lives of penconazole in cucumbers on three sites were 1.6-1.9 d,and in soil were 1.8-3.2 d.When cucumbers were treated 2-3 times with low(57.0 g/hm2,a.i.) or high(85.5 g/hm2,a.i.) dosage of penconazole,the residues in cucumbers after the last application for 1 d,3 d and 5 d,were under 0.080 mg/kg,which was safe according to the MRL(minimum required performance level) standard(0.1 mg/kg) in cucumber from CAC(Codex Alimentarius Commission),Japan or Europe.